RF power is a frequently measured quantity because other RF electrical quantities like current, voltage, and impedance are difficult to measure and quantify in RF equipment. At low frequencies, power measurement is made by interpretation of voltage and current across a known impedance. However, at higher frequencies, such as RF frequencies, the impedance changes significantly and therefore direct measurement of power is not feasible.
Traditionally, handheld RF power meters have directly measured RF power by directly transducing high frequency RF power into a DC signal, such as by using a Schottky or Gallium-Arsenide diode, and measuring the DC signal. However, the accuracy of meters using these traditional direct measurement techniques are sensitive to the measured RF signal's frequency and waveform.
Accordingly, a need exists for a handheld RF power meter that is insensitive to an RF signal's frequency or waveform.